Evaluation of the Taxonomic Status of Lesser Egyptian Jerboa, Jaculus jaculus: First Description of New Phylogroups in Tunisia.

Abstract

Simple SummaryRodents systematically represent a major issue owing to their biodiversity assessment. These micromammals exhibit phenotypic and genetic diversity and can be found in different ecosystems. The current study was undertaken to examine the morphometric and genetic patterns recently adapted by Jaculus (J.) jaculus in Tunisia. Moreover, we investigated micro-geographic clustering according to the species and/or the biotope ecosystem. Forty-six rodents were captured and analyzed for body measurements. At the genetic level, we confirmed the presence of two species, J. jaculus and J. hirtipes, but we found that each of these rodent species harbored two phylogroups that were genetically distant without any geographical and/or environmental structuring. The taxonomy of the Lesser Egyptian jerboa, Jaculus (J.) jaculus (Dipodinae subfamily), was recently reevaluated, and the taxonomic status was defined by the presence of two cryptic species, J. jaculus (Linnaeus 1758) and J. hirtipes (Lichtenstein, 1823), with a higher genetic divergence in the sympatric North African populations than in other studied parapatric populations. Using phylogenetic analysis of the cytochrome b (Cytb) gene from 46 specimens, we confirmed the new status in Tunisia; rodents were collected from two different biotopes belonging to the same locality at the ecological level (mountainous vs. Saharan) in the south of the country. The study of the eye lens weight of these specimens allowed the definition of a cutoff value (58.5 g), categorizing juveniles from adults. Moreover, this study confirmed the phylotaxonomic status of J. jaculus in Tunisia, as recently illustrated, into two distinct species, J. jaculus and J. hirtipes, and recorded for the first time the presence of two phylogroups among each of these rodent species. The lack of clear micro-geographical structure and biotope specificity between the two rodent species and their phylogroups was also highlighted.